I've lost the ability to add new issues on the plan board !

I've been using JIRA Agile OnDemand for many months now but in the past couple of days it appears something changed that has removed the ability to add new issues/stories at the bottom of upcoming sprints and the backlog. The attached screenshot shows the area where the the new issue quick entry control normally appears. The sprint in question is not active (i.e. has not been started). It no longer appears underneath the backlog section either. Nothing has been changed in terms of user roles or project config in quite some time.

...It's true that there are projects in Jira; but they are merely a way to cut off issues, to tell them apart from other sections of work and to apply rules that are specific to that team (the schemes)....